The Challenging Diagnosis of Interstitial Lung Disease in Children-One Case Report and Literature Review

Abstract

Childhood interstitial lung disease (chILD) includes a heterogeneous spectrum of rare respiratory disorders in children associated with substantial morbi-mortality. Interstitial tissue, and other pulmonary structures, epithelium, blood vessels, or pleura are involved, resulting in a restrictive lung disfunction. Respiratory symptoms set in progressively and are often subtle, making thorough clinical history and physical examination fundamental. The etiology often is obscure. The clinical presentation mimics pneumonia or asthma, leading to a diagnostic delay. Challenging diagnosis may require genetic tests, bronchoalveolar lavage, or lung biopsy. Alongside general supportive therapeutic measures, anti-inflammatory, immunosuppressive or antifibrotic agents may be used, based on data derived from adult studies. However, if accurate diagnosis and treatment are delayed, irreversible chronic respiratory failure may ensue, impacting prognosis. The most frequent chILD is hypersensitivity pneumonitis (HP), although it is rare in children. HP is associated with exposure to an environmental antigen, resulting in inflammation of the airways. Detailed antigen exposure history and identification of the inciting trigger are the cornerstones of diagnostic. This article provides the current state of chILD, revealing specific features of HP, based on a clinical case report of a patient admitted in our clinic, requiring extensive investigations for diagnosis, with a favorable long-term outcome.

Keywords: avian antigen; bronchoalveolar lavage; children; hypersensitivity pneumonitis; interstitial lung disease.

Figure 1

General diagnosis design in chILD.

Figure 2

Chest radiography showing diffuse interstitial infiltrates, predominantly perihilar.

Figure 3

Pulmonary function tests suggestive for severe restrictive and obstructive ventilatory dysfunction and reduced lung capacity for diffusing carbon monoxide.

Figure 4

Pulmonary HRCT—transverse sections showing diffuse bilateral ground-glass opacities.

Figure 5

Histopathologic exam—thoracoscopic lung biopsy, H&E stain, 100×. (A) Lung parenchyma with bridging peribronchiolar fibrosis; (B) Lung parenchyma with non-necrotizing granuloma and peribronchiolar fibrosis; (C) Lung parenchyma with interstitial fibrosis and lymphocytic infiltration; (D) Lung parenchyma with non-necrotizing granulomas and interstitial fibrosis.

Figure 6

Patient follow-up showing improvement of pulmonary function tests over the first 12 months after admission.